Terminal construction



Dec. 20, 1949 H. M. TEAGUE 2,491,879

TERMINAL CONSTRUCTION Filed March 8, 1945 id 75 4 i6 17 19 i i? f 2 5 qv/wz 69/7/9720 2/11 6- kg)? LOMM ATTUIPNE) Patented Dec. 20, 1949 TERMINAL CONSTRUCTION Hubert M. Teague, Bloomfield, N. J., assignor to Thomas A. Edison, Incorporated, West Orange, N. J a corporation of New Jersey Application March 8, 1945, Serial No. 581,666

3 Claims.

This invention relates to improved terminal constructions for batteries. As a preferred illustrative example, the invention is herein described in connection with a primary battery of the zinc anode, alkaline electrolyte, air-depolarized type.

Objects of my invention are to provide an improved lead-through terminal construction adapted for mounting on battery containers which is hermetically sealed and arranged so that the terminal per se is effectively isolated from contaminating elements of the batteries.

It is a further object to provide a terminal construction wherein the terminal per se is separated from the lead-through conductor by a conductive non-amalgam'ating means, and it is especially an object in this respect to provide an improved terminal construction for amalgamated electrodes of primary batteries wherein the terminal per se is effectively isolated from contact with mercury of the battery electrode.

It is another object to provide a terminal construction of the character described which may be preassembled with the cover of the electrical device and be then electrically connected and hermetically sealed after the cover is mounted on the container.

A further object is to provide a simple and economical construction of terminal arrangement for electrical devices wherein the aforestated objectives are fulfilled.

Other and allied objects and features of my invention will more fully appear from the following description and the appended claims.

In the description of my invention reference is had to the accompanying drawings, of which:

Figure 1 is a principally axial sectional view of a primary battery in which my invention is incorporated;

Figure 2 is a top plan view of this battery; and

Figure 3 is a sectional view taken substantially on the line 33 of Figure 2.

The battery shown in the accompanying drawings is described and claimed in the pending joint application Serial No. 570,390 of Le Roy S. Dunham and Ernest O. Jegge (abandoned and continuation-in-part application Serial No. 734,956 filed March 15, 1947, now issued as Patent No. 2,456,472), having a common assignee with the present application, and is herein described for the purpose of illustrating an application in which my invention has particular utility. This battery is a Zinc anodealkaline electrolyteairdepolarized cell having a liquid-tight container l, for example of stainless steel, provided with a cover 2 of insulating material such as rubber or suitable plastic. The container has an inwardlyturned bead 3 at the top which forms a seat for the cover. Lying against the inner Wall of the container is a sheet 4 of insulation and adjacent the inner side of this insulating sheet is a negative electrode or anode 5 made of zinc. Supported by the cover is a cylindrical positive electrode or cathode 6 which is made of a suitable carbonaceous air-depolarizing material. This cathode has a stud bolt 1 secured to the top portion thereof which forms a terminal therefor. This bolt extends through the cover and is held thereto by an external nut 8. The top portion of the cathode engages a cylindrical recess 9 in he bottom part of the cover and is held tightly at its rim against an interior shoulder Ill of this recess under pressure provided by tightening the nut 8 on the bolt 1, the joint between the cathode and the cover being closed airtight by a suitable sealing material II. From the recess 9 there extend a series of breather holes l2 through the cover for exposing the cathode to the atmosphere.

In the battery container there is a granular material l3 of dry caustic alkali preferably including in intermixture therewith an electrolyte regenerating material such as calcium hydroxide. After the electrodes are mounted in place and the material I3 is introduced into the container, the cover is sealed at its rim to the container by a suitable sealing material It. When the battery is to be put into use water is added thereto by way of an opening IS in the cover having a removable vented cap I6. Until the battery is put in use, however, the vent of the cap i6 is kept sealed by adhesive tape 16a, as are also the breather holes l2 as by adhesive tape 11, so that the material l3 will not be exposed to the elements of the air.

Mounted also on the cover is a terminal structure for the zinc anode which is referred to generally as l8. This terminal structure comprises an exterior terminal l9 made for example of brass. The zinc anode, to which this terminal connects, is commonly amalgamated so as to improve the operating characteristics of the battery. Since brass is an amalgamating material (1. e., capable of being amalgamated) and the terminal is connected through a short length of conductor to the zinc anode, there are encountered serious difficu1- ties in preventing amalgamation and consequent disintegration of the terminal. By my invention, however, the terminal is efiectively isolated from contact with mercury of the zinc anode. Also, the terminal construction is hermetically sealed to the cover-which is an important advantage in deferred-action cells containing ingredients which are to be kept out of contact with the air, such as are here describedand is arranged so that it is easy to assemble with the battery components.

In the preferred arrangement of the terminal construction according to my invention, the cover 2 is provided with an inner recess and with an adjacent outer recess 21' separated by an intervening wall 22 (Figure 3). Extending from the recess 20 through the cover is an aperture 23 to receive the terminal I9. The head of this-terminal is disposed within the recess 20 and the threaded shank of the terminal extends through the.aper- After the terminal is mounted, the inner recess 20 is filled with a sealing material 20a, such as a suitablewaxor pitch, so

ture 23 above the cover.

that no part of the terminal will be exposed to the elements Within the battery and so-that an hermetically sealed joint will be obtained between the terminal and the cover. On the exterior portion: of: the terminal there is 2. lug 24 held theretolby a nut 25. This lug-24 terminates within the outer recess 2|;

opening 2'! in the bottom wall of the outer recess 2!, this leadevvire -being for instance threaded.

The lead wire -26 is preferably made of copper l as ':copper has the advantage that it will amalgamate :with mercury from a zinc anode and,

when so amalgamated, is incapable of producing However, to prevent the'copper wire from carrying mercury'from the anode to the terminal !9, the

any local battery action with the anode.

lug 24=is made-of a non-amalgamating material which is incapable of carrying mercury, such as iron; It may be here parenthetically noted that. iron is not suitable for direct connection to the anode because iron'in the presence of an alkali electrolyte-will have local action with the zinc anode.- The iron lug .24 as herein employed is however effectively isolated from the active elements of the batteryby the sealing material 29.

A f rther advantageous feature of the terminal structure hereinabove described is that the terminal' l9 and -lug-24 may be preassembled with and, sealed to-the cover. Then as the cover is mounted on the-container the lead wire may be threaded through the opening 21 as above explained; After the cover is sealed to the container, the lead wire may be joined to the lug and the recess 2| may be filled with the sealing material 29."

It will be understood that I provide a simple and h ghly useful terminal structure for primary batteries of the character described, but that I intend no unnecessary limitation of my invention to this particular application. Rather it is submitted that the present embodiment is illustrative"and'notInecessarilylimitat ve of the invention, and that changes and modifications may bem-ade thereinwithout departure from the scope of the invention, which I endeavor to ex press according to the following claims.

I claim:

1. In abattery h'avinga container and an amal amatedelectrode: the combination of 'a cover for,saidcontainer-having a. recess in the inner Secured to the zinc anode 1 isa lead wire -26 which passes through a small side thereof and a recess in the outer side thereof ofiset from said first recess, said recesses leading into respective apertures which extend through said cover; a terminal of amalgamating material mounted in said inner recess and extending through the aperture at said inner recess into the space beyond the outer side of said cover; a first conductive memberof amalgamating material connected to said electrode and extending from the inside of said container through the other of said apertures into said outer recess; a second conductive member of non-amalgamating material joined to said first member within said outer recess and connected to an exterior portion of said terminal; and sealing means substantially filling said recesses.

2. In an electrical device having a container and an electrode therein: the combination of a cover for said container adapted to be installed after the device is assembled and having interior and exterior recesses offset from each other and apertures leading from said recesses respectively, a terminal permanently mounted in said inner recess and extending through the aperture at said inner recessinto the. space beyond said cover, means sealing said inner recess closed to seal said terminal from contact with elements within the containena conductor at the outer side of said cover secured to said terminal and terminating within said outer recessa second conductor connected permanently to said electrode and extending loosely through the aperture associated with said outer recess,:said conductors being interconnectedwithin said outer recess, and sealing means fillingssaid outer recess for sealing said second conductor to said cover and enclosing the junction of said conductors.

3. Aprimary cell comprising an amalgamated electrode, an alkaline electrolyte contacting said electrode, a first conductor connected to said electrode and of an amalgamating material free from local battery action with said electrode in the presence of said electrolyte, a terminal outside said cell of anamalgamating material, a second conductor solely connecting said first conductor to said terminal and of a metallic non-amalgamating material for preventing the transport of mercury fromsaidfirst conductor to said terminal, said secondconductor being subject to local battery action with said amalgamated electrode in the presence of said alkaline electrolyte, and means sealing said second conductor from contact with said electrolyte.

HUBERT M. TEAGUE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number I Name Date 421,169 Hewitt Feb. 11, 1890 425.818 McLaughlin Apr. 15, 1890 482.979 Knowles Sept. 20, 1 92 695.707 Bugg Mar. 18. 1902 768.175 Fritchle Aug. 23, 1904 1,. 2'7.9R5' Snyder Feb. 9, 1915 1.582.567 Yn ve Apr. 2'7, 1926 1,971,275 Rock Aug. 21, 1934 FOREIGN PATENTS Number Country Date 552,647 Great. Britain Apr. 19, 1943 

